java - AnimatedVectorDrawable in Support Library and animation of "pathData"

Question

I am using animated vectors from Support Library 23.2.0, like this:

compile 'com.android.support:support-vector-drawable:23.2.0'
compile 'com.android.support:animated-vector-drawable:23.2.0'

I am trying to animate "pathData" (morphing lines one to another). My code looks like this.

drawable/ic_done.xml:

<?xml version="1.0" encoding="utf-8"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"
    android:width="24dp"
    android:height="24dp"
    android:viewportHeight="24.0"
    android:viewportWidth="24.0">
    <path
        android:name="tick"
        android:pathData="M4.8,12L9,16.2L20,8"
        android:strokeColor="#FF000000" />
</vector>

drawable/ic_done_animated.xml:

<?xml version="1.0" encoding="utf-8"?>
<animated-vector xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:drawable="@drawable/ic_done">
    <target
        android:name="tick"
        android:animation="@animator/tick_path_animation" />
</animated-vector>

animator/tick_path_animation.xml:

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:ordering="sequentially">
    <objectAnimator
        android:duration="200"
        android:propertyName="pathData"
        android:valueFrom="M4.8,12L4.8,12L4.8,12"
        android:valueTo="M4.8,12L9,16.2L9,16.2"
        android:valueType="pathType" />
    <objectAnimator
        android:duration="200"
        android:propertyName="pathData"
        android:valueFrom="M4.8,12L9,16.2L9,16.2"
        android:valueTo="M4.8,12L9,16.2L20,8"
        android:valueType="pathType" />
</set>

Java code:

ImageView vImgAnimated = findByViewId(R.id.img);
AnimatedVectorDrawableCompat animatedVector = AnimatedVectorDrawableCompat.create(getContext(), R.drawable.ic_done_animated);
vImgAnimated.setImageDrawable(animatedVector);
animatedVector.start();

It works well on newer device with API level 21 but I have a problem on device with API level 16:

java.lang.NumberFormatException: Invalid int: "M4.8,12L4.8,12L4.8,12"
    at java.lang.Integer.invalidInt(Integer.java:138)
    at java.lang.Integer.parse(Integer.java:375)
    at java.lang.Integer.parseInt(Integer.java:366)
    at com.android.internal.util.XmlUtils.convertValueToInt(XmlUtils.java:123)
    at android.content.res.TypedArray.getInt(TypedArray.java:254)
    at android.animation.AnimatorInflater.loadAnimator(AnimatorInflater.java:258)
    at android.animation.AnimatorInflater.loadObjectAnimator(AnimatorInflater.java:161)
    at android.animation.AnimatorInflater.createAnimatorFromXml(AnimatorInflater.java:117)
    at android.animation.AnimatorInflater.createAnimatorFromXml(AnimatorInflater.java:126)
    at android.animation.AnimatorInflater.createAnimatorFromXml(AnimatorInflater.java:93)
    at android.animation.AnimatorInflater.loadAnimator(AnimatorInflater.java:72)
    at android.support.graphics.drawable.AnimatedVectorDrawableCompat.inflate(AnimatedVectorDrawableCompat.java:377)
    at android.support.graphics.drawable.AnimatedVectorDrawableCompat.createFromXmlInner(AnimatedVectorDrawableCompat.java:162)
    at android.support.graphics.drawable.AnimatedVectorDrawableCompat.create(AnimatedVectorDrawableCompat.java:142)

According to an article android-support-library-232 the animated vectors (AnimatedVectorDrawableCompat) should be supported back to API level 11.

It looks like it fails while reading valueFrom attribute from tick_path_animation.xml. This attribute type "pathType" is probably not supported (yet?). Any idea how to solve this?

Answer 1

Sorry, this will not work with the current version of the Support Library(23.2.0).

See Chris Banes article.

There are also some limitations to what kind of things animated vectors can do when running on platforms < API 21. The following are the things which do not work currently on those platforms:

Path Morphing (PathType evaluator). This is used for morphing one path into another path.

Path Interpolation. This is used to defined a flexible interpolator (represented as a path) instead of the system defined ones like LinearInterpolator.

Move along path. This is rarely used. The geometry object can move around, along an arbitrary path.

So animating the pathData, or 'Path Morphing' isn't currently supported.

Update:
Frank's comment:

This is finally fixed in support lib 25.4.0 (June 2017): "Path morphing and path interpolation are supported in AnimatedVectorDrawableCompat"